Converted DatabaseBase::mTrxAtomicLevels to an array

* This simplifies the code and cleans up __construct()
  a bit while also making it less likely to cause
  trouble with unit testing mocks.
* Also add a sanity mTrxLevel check around usage
  of mTrxAtomicLevels in the one place it was missing

Change-Id: Ia0a7f22f5c27b3d4d8b51e04629f42a1ed9c3993

diff --git a/includes/db/Database.php b/includes/db/Database.php
index 4bbb491..05d1934 100644 (file)
--- a/includes/db/Database.php
+++ b/includes/db/Database.php
@@ -124,9 +124,9 @@ abstract class DatabaseBase implements IDatabase {
        /**
         * Array of levels of atomicity within transactions
         *
-        * @var SplStack
+        * @var array
         */
-       private $mTrxAtomicLevels;
+       private $mTrxAtomicLevels = array();
 
        /**
         * Record if the current transaction was started implicitly by DatabaseBase::startAtomic
@@ -609,8 +609,6 @@ abstract class DatabaseBase implements IDatabase {
        function __construct( array $params ) {
                global $wgDBprefix, $wgDBmwschema, $wgCommandLineMode, $wgDebugDBTransactions;
 
-               $this->mTrxAtomicLevels = new SplStack;
-
                $server = $params['host'];
                $user = $params['user'];
                $password = $params['password'];
@@ -3395,7 +3393,7 @@ abstract class DatabaseBase implements IDatabase {
                        }
                }
 
-               $this->mTrxAtomicLevels->push( $fname );
+               $this->mTrxAtomicLevels[] = $fname;
        }
 
        /**
@@ -3413,13 +3411,13 @@ abstract class DatabaseBase implements IDatabase {
                if ( !$this->mTrxLevel ) {
                        throw new DBUnexpectedError( $this, 'No atomic transaction is open.' );
                }
-               if ( $this->mTrxAtomicLevels->isEmpty() ||
-                       $this->mTrxAtomicLevels->pop() !== $fname
+               if ( !$this->mTrxAtomicLevels ||
+                       array_pop( $this->mTrxAtomicLevels ) !== $fname
                ) {
                        throw new DBUnexpectedError( $this, 'Invalid atomic section ended.' );
                }
 
-               if ( $this->mTrxAtomicLevels->isEmpty() && $this->mTrxAutomaticAtomic ) {
+               if ( !$this->mTrxAtomicLevels && $this->mTrxAutomaticAtomic ) {
                        $this->commit( $fname, 'flush' );
                }
        }
@@ -3443,7 +3441,7 @@ abstract class DatabaseBase implements IDatabase {
                global $wgDebugDBTransactions;
 
                if ( $this->mTrxLevel ) { // implicit commit
-                       if ( !$this->mTrxAtomicLevels->isEmpty() ) {
+                       if ( $this->mTrxAtomicLevels ) {
                                // If the current transaction was an automatic atomic one, then we definitely have
                                // a problem. Same if there is any unclosed atomic level.
                                throw new DBUnexpectedError( $this,
@@ -3491,7 +3489,7 @@ abstract class DatabaseBase implements IDatabase {
                $this->mTrxDoneWrites = false;
                $this->mTrxAutomatic = false;
                $this->mTrxAutomaticAtomic = false;
-               $this->mTrxAtomicLevels = new SplStack;
+               $this->mTrxAtomicLevels = array();
                $this->mTrxIdleCallbacks = array();
                $this->mTrxPreCommitCallbacks = array();
                $this->mTrxShortId = wfRandomString( 12 );
@@ -3524,7 +3522,7 @@ abstract class DatabaseBase implements IDatabase {
         * @throws DBUnexpectedError
         */
        final public function commit( $fname = __METHOD__, $flush = '' ) {
-               if ( !$this->mTrxAtomicLevels->isEmpty() ) {
+               if ( $this->mTrxLevel && $this->mTrxAtomicLevels ) {
                        // There are still atomic sections open. This cannot be ignored
                        throw new DBUnexpectedError(
                                $this,
@@ -3610,7 +3608,7 @@ abstract class DatabaseBase implements IDatabase {
                $this->doRollback( $fname );
                $this->mTrxIdleCallbacks = array(); // cancel
                $this->mTrxPreCommitCallbacks = array(); // cancel
-               $this->mTrxAtomicLevels = new SplStack;
+               $this->mTrxAtomicLevels = array();
                if ( $this->mTrxDoneWrites ) {
                        $this->getTransactionProfiler()->transactionWritingOut(
                                $this->mServer, $this->mDBname, $this->mTrxShortId );